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Blower not working for ac or heat

So our heat/ac has not been working for over a year. I think it might be an electrical issue. it used to work every once in a while, but now, its not working at all. we just replaced the blower motor, which I knew we shouldn’t have done b/c I think we need a regulator? has anybody dealt with this issue?

our odotmeter is not working as well and some lights are turned on in the dashboard which should not be on as well. (which is why I think it is an electrical problem.)

thanks for your help!!!

Why did you do something you knew you shouldn’t have done? This is a more serious and profound problem than your blower not working.

Apply 12V to the old motor: does it blow? Is it open?

What voltage do you measure? If the regulator isn’t working, just about every electrical thing should fail.

Odometers are mechanical, not electrical.

What lights on your dashboard are on that shouldn’t be? Could they possibly be telling you that your oil pressure is low (etc.)?

are you sure? they seem to be electronic in modern cars. We don’t know the year of this Buick.

By the early 2000s, mechanical odometers would be phased out on cars from major manufacturers. The Pontiac Grand Prix was the last GM car sold in the USA to offer a mechanical odometer in 2003, the Canadian-built Ford Crown Victoria and Mercury Grand Marquis were the very last Fords sold with one in 2005.

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+1. Mechanical odometers have largely disappeared from new cars. Simulated “gages” are much cheaper to make and install.

The blower motor is a 12VDC motor. Its speed is regulated by passing the12VDC through a stepped resistive network that “drops” voltage such that the motor sees a lesser voltage. It’s generally that network that needs replacement. The fan itself can be unplugged and tested using a 9V transistor radio battery. Or two 6VDC batteries in series. That’s how I do it.

The bad news is that on many modern car a lot of these controls are incorporated into a “Body Control Module”. You might want to ask your dealer’s parts window guy for this information. He can look it up for you.

It would help to look at a wiring schematic but I would suspect either the blower resister/blower control module or the HVAC programmer.

I would check out the blower motor resistor as @bing suggested, Your other prblems are unrelated imhop. The variable resistors are inexpensive, and usually not to hard to replace.

Whoops! Shows how out-of-date I am.

You think the alternator’s voltage regulator is faulty? That’s pretty easy to test for yourself if you have a volt meter. Connect your volt meter to the + and - terminals on the battery on the 20 vdc scale. With the engine off it should read about 12.5 volts. Now start the engine. It should now read 13.5 - 15.5 volts. And slowly go down towards 13-13.5 volts the longer the engine runs. It that all checks out, unlikely to be a faulty alternator voltage regulator. Not saying you don’t have an assortment of electrical problems though, hard to say over the internet. The heat blower problem is probably not a part of a systemic electrical problem though, it’s most likely a problem with that circuit only. Heater blowers are a pretty common failure item we here about here, usually it is the blower cage is struck due to debris, the motor itself has failed, or the blower resistor pack, or the blower control module.

Exactly which regulator are you talking about

The voltage regulator, which is often part of the alternator?

Or some other regulator?

How about telling us which lights are on, and WHY you feel they shouldn’t be

Please define “not working”

mileage doesn’t grow over time

odometer backlighting inop, so you can’t read the mileage

Is the speedometer functional?

Bc my dad pressured me into doing it. I know stupid, but that’s it.

Not a regulator, a relay. Sorry, confused the two. Relay bc the odotomter decides to light up when the blower works. I have a low tire light on when it ahpuldnt be on, door/teunk light is on. When those turn off, the blower works. The speedometer is working an functional.

You’ve definiitely got some electrical problems, but I’m not sure they’re all because of one root cause

Your tire pressure light is probably on because of low tire pressure or a faulty sensor

As far as the door/trunk light on . . . are you saying the red warning in the cluster is lit, indicating a door or the trunk is open?

Or are you saying the trunk light and/or dome light won’t turn off, no matter what?

What relay are you talking about?

As far as the blower goes, the lower speeds go through the blower resistor pack. And high speed goes through the relay.

That’s very different: if your father told you to do it, at least you learn the valuable lesson that fathers don’t know everything, which you can remember when you’re one.

db4690, the tire pressure light is always on, doesn’t matter if I put air in it or not. I think its a faulty sensor. the door trunk light is on no matter what. the lower speeds and higher speeds do not work at all. so what do you think I should try it next?

Well, which is it?

The trunk light is staying on?

The dome light is staying on, as if the doors were opened?

The warning in the cluster is illuminated, indicating that a door and/or trunk lid is open?

It sounds like you do have a faulty tire pressure sensor

What year is your Regal? I’m asking because on some cars, the blower resistor and relay are combined into one unit. What ac system do you have? Manual ac controls? Automatic climate control?

Lack of heat can be a blend door actuator problem too. Not an uncommon thing in GM vehicles from the posts we get here.

The light is for both. I have a 99

Have you tried resetting it?:
Picture 1

Okay, now we’ve established you have a 1999 Regal

You still haven’t answered whether you have manual ac controls or automatic climate control

If you have manual ac controls, this may be your problem


If you have automatic climate controls, this may be your problem


They’re manual.